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The graph composed of all points with the solution of equation 3x + y = 5 as coordinates is a straight line () A.y=3x+5 B.y=3x-5 C.y=-3x+5 D.-3x-5
C
In the rectangular coordinate system, there are two straight lines y = 3x-2 and y = - 4x + 3. Their intersection point is a. the two straight lines intersect with the Y axis at points B and C respectively
(1) Using image method to solve equations {3x-y = 2 and 4x + y = 3
(2) Finding the area of triangle ABC
Let 3x-2 = - 4x + 3
x=5/7
Let x = 0
y=-2,3
S = 3 / 56
The equation with unique solution is 3x + 2Y. Why?
There should be a detailed process
The only solution is 3x + 2Y = 1
You can consider this: 3x-2y = 1 has innumerable solutions, if you add an X, y equation restriction, the two become binary linear equations! 1, if the coefficients of the equations are multiple relations, then there are innumerable solutions. 2, if the coefficients of the equations are not multiple relations, then there is a unique solution
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